1. Field of the Invention
The present invention relates to a latch which can releasably anchor a well tool at a preselected downhole location. One embodiment of the invention, disclosed in this application, is used to releasably latch one end of a tubing string to a well packer at a downhole location within a well bore.
2. Description of the Prior Art
Many oil and gas wells are completed with two or more production tubing strings to conduct well fluids from downhole producing formations to the well surface. If desired, both production tubing strings can be installed and removed simultaneously from the well bore as taught by U.S. Pat. No. 4,236,734 invented by Mansour Ahangarzadeh. However, many well operators prefer to handle only one string of production tubing at a time.
Typically, a well packer is attached to one string of production tubing at the well surface and then lowered to the desired downhole location within the well bore. A second string of production tubing is later inserted from the well surface into the well bore and engaged with the well packer. The well packer may be anchored within the well bore either before or after engagement by the second production tubing string. U.S. Pat. No. 3,161,127 to P. S. Sizer provides a detailed description of this method for installing a well packer and dual production tubing strings within a well bore. Additional examples of multiple conduit well completions are shown in U.S. Pat. No. 3,326,292 to C. R. Young et al.; U.S. Pat. No. 3,330,360 to C. R. Young; U.S. Pat. Nos. 3,381,752 and 3,391,741 to T. L. Elliston; and U.S. Pat. No. 3,934,648 to Amareswar Amancharla et al. The above listed patents are incorporated by reference for all purposes within this application.